DZ03G's are cheaper than R888's by £10 iirc (in 15s) so can't see why thay be more expensive in diffrent sizes, As for Toyo Proxies R888 don't waste you money on them at this time of year! Anything below 10c kills the tyres and because of the lack of tread there deadly on standing water and a death trap in snow.
As for all the others said (havn't look at them all posted) but dont by a single one there fucking summer tyres which are a total watse of money duing this time of year because the rubber gets to hard. Just by some nice winter tyres and thay will out perform every trye post (unless someone said a winter tyre that is lol)